Synergistic effects of nano SnO2 and TiO2 on the mechanical and antibacterial properties of HDPE

This research dealt with the synthesis of both nano stannic oxide (SnO₂) and titanium dioxide (TiO₂) nanoparticles and how their addition to high-density polyethylene (HDPE) with 5 and 3%, respectively, can affect its properties from structural, mechanical, and permeability properties, besides the antibacterial activity. The possible modulation of HDPE plastic-elastic mechanical behavior was explored for each nanoparticle type and concentration. Adding 3% SnO₂ to HDPE notably improved mechanical properties in terms of toughness from 12.1 to 16.6 × 106 (J/m3), fracture strength from 1.76 to 15.29 (MPa), and impact strength from 61.1 to 69.2 (J/m2), besides increasing the ductility of HDPE via decreasing the Young’s modulus from 1.75 to 1.62 (GPa). This may be ascribed to the homogeneous distributions of nano-sized inorganic fillers. This made the HDPE have unique superior properties, making it suited for applications that need engineering designs. Similarly, adding a little amount of TiO₂ (1 wt%) improved attributes like toughness to 12.30 × 106 (J/m3) and fracture strength to 11.29 (MPa), impact strength to 63.1 (J/m2). The observed changes in the tested mechanical properties were influenced by filler dispersion, interfacial interaction between matrix and nano-filler, and matrix restriction mechanisms. On the contrary, high TiO2 filler loading (3% wt.) resulted in agglomeration and interfacial structural defects, leading to deterioration of the HDPE’s mechanical properties. The enhanced properties of the HDPE-nano SnO₂ composites encouraged the production of films of these compositions to study their water vapor and Oxygen permeabilities, besides the antibacterial activity. Increasing nano SnO2 percentage in HDPE matrix enhanced antibacterial functioning against both E. coli and MRSA, as mirrored by larger inhibition zones and lower obtained MIC values.